The manufacturing process in the semiconductor industry is divided into several stages, including a chip (IC) design stage, a wafer fabrication stage (Wafer Fab), a wafer probing stage and a wafer packaging stage. In the wafer probing stage, a probe is used to test all dies of the wafer. That is, a probe formed of a metal pin is installed on a test head, and the probe is contacted with a pad on the die to test the electrical properties of the die. Moreover, the dies were not able to pass/meet test criteria, then the test are printed with ink marks. After the wafer with plural individual dies is tested, the dies with the marks are discarded, and the subsequent process is not performed. Meanwhile, the wafer probing stage is completed.
Generally, the wafer tester uses a channel board to test the wafer. According to the type of the wafer to be tested, a corresponding channel board is used. Moreover, the wafer tester has one or plural insertion slots for inserting one or plural channel boards therein. Conventionally, the channel board has 32 channels, 64 channels, 128 channels, or more than 128 channels . . . , etc.
Moreover, according to the type of the wafer, the wafer tester and the channel board provide corresponding test parameters to the dies of the wafer to judge whether the dies of the wafer are normally operated. Conventionally, after the test parameters of the wafer tester are set by the original factory/supplier, the test parameters of the wafer tester are provided from the original factory/supplier. However, because of improper tester installation, parts replacement, part aging or other causes, the test parameters set by the original factory/supplier cannot be continuously used to test the wafer. Under this circumstance, the wafer perhaps fails the test.
For solving the above drawbacks, it is necessary to notify the maintenance engineer of the original factory to re-calibrate the tester and set the suitable test parameters. However, since the testing procedure has to be interrupted during the re-calibrating process, the testing efficiency is largely reduced. Moreover, even if the tester has been calibrated, the test parameters are possibly unsatisfied because the conventional technology doses not provide the calibrating comparison function about the test parameters of the channel board. That is, after the tested is calibrated, an improper test result is possibly generated because the test parameters of the channel board cannot be calibrated.